60-07-07 VICKERS: Amdt. 116 Part 507 Federal Register March 23, 1960. Applies to Viscount Model 745D Serial Numbers 103 to 107 Inclusive, 109 to 134 Inclusive, 136 to 139 Inclusive, 183, 184, 185, 191, 198 to 217 Inclusive, 231, 232, 233, 234, 285, 334.
Compliance required as indicated.
As a result of instances of corrosion which have been found to occur in the skin to wing spar boom attachment holes, it is necessary that aircraft built to Modification D.953 standard have oversized skin to spar attachment bolts installed in the inner and outer top booms (unbushed) in accordance with part (e) of Vickers Modification Bulletin No. D.2081. The oversize bolts are of S.80 material cadmium plated either 1/32-inch or 1/16-inch oversize as required, depending upon the state of the holes; this is determined by the inspections detailed in the Preliminary Technical Leaflet 197. Thickol is used as sealant when the oversize bolts are fitted.
Compliance:
(a) Bolt installation in accordance with Mod. D.2081, part (e), is required within 10,000 hours' time in service or five calendar years from the date of aircraft manufacture, whichever occurs first, unless a satisfactory sampling inspection as covered in (b) is accomplished.
(b) Bolt installation in accordance with Mod. D.2081, part (e), may be accomplished by an operator within 13,000 hours' time in service provided a satisfactory sampling inspection for corrosion is conducted on five complete aircraft sets of top skin to spar attachment bolts. This sampling inspection must be conducted on the operator's aircraft which have between 9,000 and 10,000 hours' time in service. Corresponding spar bolt holes also must be inspected for corrosion when the bolts are removed. If any corrosion is found on the bolts or in the spar bolt holes, Mod. D.2081, part (e) must be accomplished within 10,000 hour's time in service or five calendar years from the date of aircraft manufacture, whichever occurs first.(Modification Bulletin D.2081 and Preliminary Technical Leaflet No. 197 Issue 5 (700 Series) cover this subject.
This supersedes AD 60-01-08.
Revised March 13, 1964.